Ventilator to tracheotomy tube coupling

ABSTRACT

A coupling for connecting an air supply to a respiratory support device has a latching mechanism which prevents the coupling from inadvertently axially displacing from the respiratory support device after they have been mated in a pneumatically discrete path. Non-axial forces are used to disengage the coupling from the respiratory support device. The coupling may include a trailing end adapter which permits rotation of the coupling relative to the air supply rather than to the respiratory support device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 11/899,221 filed Sep. 5, 2007 (pending), which is acontinuation-in-part application of U.S. application Ser. No. 11/731,538filed Mar. 30, 2007 (now U.S. Pat. No. 8,485,193), which is acontinuation-in-part of U.S. application Ser. No. 11/348,199 filed Feb.2, 2006 (abandoned), all of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

This invention relates generally to medical equipment and moreparticularly concerns devices used to connect ventilators to tracheotomytubes.

For adult patients, two-piece tracheotomy tubes having inner and outercannulas are presently in common use. The outer cannula is inserted intothe patient's windpipe and the inner cannula is inserted into or removedfrom the outer cannula for use or for replacement, cleaning ordisinfecting, respectively. The outer cannula of these two-piece deviceshas a collar on its trailing end which is configured to be positivelyengaged with a collar on the leading end of the inner cannula. Thecannulas cannot be disengaged from each other affirmative release oftheir positive engagement. The trailing end of the combined cannulas hasa tapered tubular extension which plugs into or into which is plugged,depending on the diameter of the tubular extension of the particulartracheotomy tube, the leading end of a flexible connector. The trailingend of the flexible connector is connected to a tube extending from theventilator or other external equipment. The present tapered tubularextension connection to the ventilator is dependent on mere insertion ofa tapered tube into a constant diameter tube in the hope of achieving asnug fit. To assist in making this connection, the flexible connectorshave annular flanges with significantly wider diameters than the tubularportions of the connectors so as to facilitate manipulation of theconnectors with the thumb and forefinger.

For children, a smaller, one piece tracheotomy tube is made from a verysoft, pliant material. The entire tracheotomy tube must be frequentlyremoved, at least once a week, from the child's trachea, cleaned anddisinfected and reinserted into the trachea. The same flanged flexibleconnector used with the adult devices is also used with the children'sdevices. The tapered tubular extension of the children's tracheotomytube is integral with the pliant tracheotomy tube and has a hard plasticouter sleeve which is inserted directly into the flexible connector. Anannular flange on the trailing end of the tubular extension of thechild's tracheotomy tube holds the hard plastic sleeve in place on theextension.

Because of their structural configuration and operational steps, thereare some problems inherent in the known one or two piece tracheotomytubes, in the known flexible connectors and in their combination.

One set of problems is related to the comfort of the patient. Theprofile of the flanged flexible connectors, falling generally betweenthe underside of the patient's chin and the patient's chest, fosters abreakdown of skin and tissue on the chin or chest, depending on the headmovements of the patient. This is especially true for children, theirchin-to-chest cavity being comparatively small. This concern issometimes addressed by after-market removal of all or a portion of theflange, but this solution generally results in a damaged connector,increasing the likelihood of infection-causing secretions and alsobecomes less secure due to removal of the firm portion of the connector.Also, the manipulation of the flange to connect or disconnect theconnector to or from the tubular extension can cause considerablediscomfort to the patient, since this often requires the application ofmanual pressure to the patient's neck, chin or chest. It is commonpractice to extend rubber bands from one side of a neck plate on thetracheotomy tube collar to the flexible connector and back to the otherside of the neck plate in an effort to hold the flexible connector inplace, but the rubber bands are likely either too elastic or tooinelastic to properly accomplish this purpose. While a child'stracheotomy tube is smaller than an adult's, the available space betweenthe chin and chest is significantly smaller and the flexible connectorflange is the same size as used for adults, so the smaller deviceaffords no relief for the connector flange related comfort problems.And, since the child's tracheotomy tubes are of one piece construction,the force necessary to disconnect the flexible connector may be directlyapplied to the patient's neck or windpipe.

A second set of problems is related directly to the ability, orinability, of the system to accomplish its primary purpose of keepingthe patient's trachea connected to the ventilator. To begin with,tapered connections tend to easily separate in the best ofcircumstances, there being minimal surface contact between the taperedand constant diameter components. Moreover, the connector andtracheotomy tube parts are always wet and slippery due to the verynature of their application and are not very tightly mated because ofthe neck pressure problems. The end result is a connection so tenuousthat a mere sneeze, cough or turn or tip of the head can cause theconnector and the tapered tubular extension to separate, defeating theoperation of the system. Even without a sneeze, cough, turn or tip, theflange itself functions as a lever against the chin or chest in responseto the patient's head movements, and the reciprocal levering by theflange will eventually cause the connector and the tubular extension todisconnect.

A third set of problems concerns the performance of the medical staff asa result of these other problems. The inherent comfort issues result inmore pains-taking, time-consuming effort by the staff in an effort toreduce the impact of these discomforts on the patient. And, because ofthe ease of inadvertent disconnection of the system, the staffunnecessarily spends valuable time monitoring and reconnecting theconnectors to the tubular extensions of the tracheotomy tubes.

It is, therefore, a primary object of this invention to provide animproved tracheotomy tube coupling. Another object of this invention isto provide a tracheotomy tube coupling which reduces a likelihood ofassociated patient discomfort. It is also an object of this invention toprovide a tracheotomy tube coupling which is more suitably profiled forpositioning between a patient's chin and chest. Still another object ofthis invention is to provide a tracheotomy tube coupling which isprofiled to reduce a likelihood of skin or tissue breakdown on apatient's chin and chest. A further object of this invention is toprovide a tracheotomy tube coupling which simplifies manipulation of thecoupling in relation to the patient. Yet another object of thisinvention to provide a tracheotomy tube coupling which reduces alikelihood of exertion of discomforting pressure on the chin, neck,chest or windpipe of a patient during connection or disconnection of thecoupling from the tracheotomy tube. An additional object of thisinvention is to provide a tracheotomy tube coupling which makesinadvertent disconnection of the tracheotomy tube from the connectedmedical equipment less likely. Another object of this invention is toprovide a tracheotomy tube coupling which does not rely on tapered toconstant diameter connections to maintain connection between thetracheotomy tube and its related equipment. It is also an object of thisinvention to provide a tracheotomy tube coupling which is profiled toreduce a likelihood that the coupling will operate as aself-disconnecting lever. Still another object of this invention toprovide a tracheotomy tube coupling which can be easily connected anddisconnected from the tracheotomy tube by the medical staff. A furtherobject of this invention is to provide a tracheotomy tube coupling whichcan reduce the time expended by the medical staff to monitor andmaintain the coupling connections. Yet another object of this inventionis to provide a tracheotomy tube coupling which facilitates more rapiddisassembly and reassembly of associated components from the tracheotomytube for cleaning and disinfecting purposes.

SUMMARY OF THE INVENTION

In accordance with the invention, a coupling is provided for connectinga ventilator tube to a tracheotomy tube. The ventilator tube has aconnector at its leading end and the tracheotomy tube has a taperedtubular extension on its trailing end. The coupling is a preferablyexpandable, flexible tubular member with a first adapter on its trailingend for connecting its trailing end in a pneumatic flow path to theventilator tube leading end connector and a second adapter on itsleading end for mating its leading end in a pneumatic flow path with thetrailing end of the tracheotomy tube. The second adapter has a latchingmechanism for engaging the leading end of the coupling to thetracheotomy tube to prevent the leading end of the tubular member fromaxially displacing from the trailing end of the tracheotomy tube afterthey have been mated in the pneumatic flow path. An unlatching mechanismis provided for disengaging the latching mechanism from the tracheotomytube so as to permit the leading end of the tubular member to axiallydisplace from the trailing end of the tracheotomy tube. The unlatchingmechanism is operated by non-axial forces so that the coupling can bedisengaged from the tracheotomy tube without exertion of excessive axialforce on the patient's neck.

Some known adult tracheotomy tubes have an inner cannula inserted into atrailing end of an outer cannula with the tubular extension on thetrailing end of the inner cannula. For such tracheotomy tubes, thecoupling tubular member has a first means on its leading end for matingthe tubular member in the pneumatic flow path with the tubular extensionof the inner cannula which is operable by motion of the mating means ina generally axial direction relative to the tubular extension. A secondmeans is provided on the mating means for engaging with the outercannula during mating to prevent the leading end of the tubular memberfrom axially displacing from the tubular extension after mating. A thirdmeans is provided on the inner cannula for disengaging the engagingmeans from the outer cannula by application of force to the mating meansin other than the generally axial direction to permit the leading end ofthe tubular member to axially displace from the tubular extension of theinner cannula. Typically, the trailing end of the outer cannula hasopposed annular flanges and the engaging means consists of opposed meansfor resiliently snapping over the flanges. The disengaging meansconsists of means on the inner cannula for spreading the opposed flangesduring rotational motion of the mating means about a longitudinal axisof the tubular member.

Other known adult tracheotomy tubes have an inner cannula inserted intoa trailing end of an outer cannula with the tubular extension on thetrailing end of the inner cannula. For such tracheotomy tubes, thecoupling tubular member has a first means on a leading end of thetubular member for mating the tubular member in the pneumatic flow pathwith the tubular extension of the outer cannula by motion of the matingmeans in a generally axial direction relative to the tubular extension.A second means is provided on the mating means for engaging with theouter cannula during mating to prevent the tubular member from axiallydisplacing from the tubular extension after mating. A third means isprovided on the outer cannula which is operable by application of forceon the mating means in a direction other than the generally axialdirection for disengaging the engaging means from the outer cannula topermit the tubular member to axially displace from the tubular extensionof the outer cannula. Typically, the trailing end of the outer cannulahas annularly opposed flat notches. The disengaging means consists ofmeans on the outer cannula for spreading the opposed flanges duringrotational motion of the mating means about a longitudinal axis of thetubular member.

Known child tracheotomy tubes have a tubular extension on their trailingend. For such tracheotomy tubes, the coupling tubular member has a firstmeans for mating the leading end of the tubular member in the pneumaticflow path with the tubular extension of the tracheotomy tube by motionof the mating means in a generally axial direction relative to thetubular extension. A second means is provided on the mating means forengaging with the tracheotomy tube to prevent the leading end of thetubular member from axially displacing from the tubular extension aftermating. A third means is provided on the mating means which is operableby application of force on the mating means in other than the generallyaxial direction for disengaging the engaging means from the tracheotomytube to permit the tubular member to axially displace from the tubularextension of the tracheotomy tube. The mating means consists of a nozzleinsertable into the tubular extension. The engaging means consists of aclamshell, the clamshell and the tubular extension having complementarythree-dimensional surfaces which prevent axial displacement of theclamshell from the tubular extension gripped therein. Half of theclamshell has diametrically opposite lugs and another half of theclamshell has diametrically opposite fingers which resiliently snap overthe lugs when the clamshell is closed. The disengaging means consists ofmeans on the fingers for spreading the fingers in response to inwardradial pressure on the spreading means to release the lugs.

An improved child's tracheotomy tube has an arcuate soft tube cannulawith a neck plate on its trailing end. The neck plate has a passagewayaligned with the cannula passageway and an annular ring on its trailingside which extends the passageway. A tubular extension trails from theannular ring to further extend the passageway. Preferably, the tubularextension is formed using a soft inner tube and a hard outer sleevepermanently fused to the soft inner tube. The annular ring has at leastone, and preferably three, circumferential sets of at least twodisplaced serrations in its outer wall. Preferably, the serrations areequally displaced on the circumference, for example two diametricallyopposed serrations, with corresponding serrations of eachcircumferential set being aligned on parallel diameters of the annularring with the diameters being horizontal in relation to a vertical planebisecting the arcuate cannula.

To connect the improved child's tracheotomy tube to a ventilator tube,the coupling provided has a tubular member adapted at its trailing endfor connection in a pneumatic flow path to the ventilator tube leadingend connector. The leading end of tubular member is adapted for matingthe tubular member in the pneumatic flow path with the tubular extensionof the tracheotomy tube by motion of the mating means in a generallyaxial direction relative to the tubular extension. The leading end ofthe tubular member is further adapted for engaging with one of thecircumferential sets of serrations to prevent the leading end of thetubular member from axially displacing from the tubular extension aftermating. The leading end of the tubular member is further adapted to beoperable by application of force in other than the generally axialdirection for disengaging the leading end of the tubular member from theengaged circumferential set of serrations to permit the leading end ofthe tubular member to be axially displaced from the tubular extension ofthe tracheotomy tube. Preferably, the trailing end adaptation of thetubular member is a hard annular ring on its trailing end, the ringhaving a tubular concentric rearward extension, a sleeve mounted forrotation on the extension and a stop mechanism on the extension forpreventing the sleeve from axially displacing from the extension. Thissleeve-on-extension configuration of the of the coupling allowsrotational forces exerted on the tracheotomy system to be more likelydissipated at the ventilator end rather than the tracheotomy tube end ofthe system. Preferably, the leading end mating adaptation is a hardsleeve of inner diameter sized to axially receive the tracheotomy tubetubular extension with the trailing face of the tracheotomy tubeextension abutting the trailing interior annular wall of the sleeve.Thus, axial motion is required only for initiation of abutting contact,reducing the likelihood of exertion of such axial force as might berequired to create a frictionally tight locking fit. Preferably, theleading end engaging adaptation is a circumferential set of at least twofingers resiliently mounted on and oriented forward of the sleeve forseating in one of the circumferential sets of displaced serrations onthe tracheotomy tube annular ring when the trailing face of thetracheotomy tube tubular extension abuts the trailing interior annularwall of the sleeve. Thus, the force exerted to engage the components isprimarily radial rather than axial or rotational, reducing thelikelihood of exertion of excessive axial force on the system. It isalso preferred that disengaging adaptation be squeeze plates on thefingers for radially displacing the fingers to release them from theengaged set of serrations in response to radially inward pressure on thesqueeze plates. Thus, the force exerted to disengage the components isalso primarily radial rather than axial or rotational, reducing thelikelihood of exertion of excessive axial force on the system.

A different embodiment of the coupling could be used to connect an airsupply to any of a variety of respiratory support devices which areprovided with radially outwardly extending flanges proximate theirtrailing end. The coupling would include the longitudinally flexingtubular member with a first adapter on its trailing end for connectingits trailing end in a pneumatic flow path to the air supply and a secondadapter on its leading end for mating its leading end in the pneumaticflow path with the respiratory support device by motion of the secondadapter in a generally axial direction toward the respiratory supportdevice bringing a leading face of the flexing tubular member intoabutment with a trailing face of a trailing end of the respiratorysupport device. A mechanism on the second adapter engages with theflanges of the respiratory support device when the flexing tubularmember and the trailing face of the respiratory support device are inabutment, thus preventing the flexing tubular member from axiallydisplacing from the respiratory support device. The engaging mechanismincludes a mechanism co-operable with the respiratory support deviceflanges to disengage the engaging mechanism from the respiratory supportdevice flanges by rotational movement of the second adapter relative tothe respiratory support device, permitting the flexing tubular member toaxially displace from the respiratory support device. Preferably, if anouter longitudinal wall of the respiratory support device is tapered, aninner longitudinal wall of the second adapter will be tapered so as tocome into abutment with the tapered wall of the respiratory supportdevice during mating of the coupling with the respiratory supportdevice. Such a respiratory support device could, for example, be atracheotomy tube outer cannula with radially outwardly extending flangesproximate its trailing end. In this application, the coupling wouldfurther include an inner cannula with a tubular extension on itstrailing end with fingers resiliently pivoted on the perimeter of thetubular extension which will snap over the outer cannula flanges when aleading face of said tubular extension comes into abutment with atrailing face of the outer cannula. A pair of radially outwardlyextending flanges angularly oriented between and trailing behind thefingers would be co-operable with the engaging mechanism of the secondadapter of the coupling. The fingers prevent axial displacement of theinner cannula from the outer cannula and the engaging mechanism preventsthe coupling from axially displacing from the inner cannula. Theengaging mechanism includes a mechanism co-operable with the innercannula flanges to disengage the engaging mechanism from the innercannula flanges by rotational movement of the second adapter relative tothe inner cannula tubular extension so as to permit the flexing tubularmember to axially displace from the inner cannula tubular extension. Theouter longitudinal wall of the inner cannula tubular extension and theinner longitudinal wall of the second adapter are preferably tapered sothat they come into abutment during mating of the coupling with theinner cannula.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the invention will become apparent uponreading the following detailed description and upon reference to thedrawings in which:

FIG. 1 is a perspective view of a first type of known tracheotomy tubeouter cannula;

FIG. 2 is a perspective view of a first embodiment of an inner cannulafor use with the outer cannula of FIG. 1;

FIG. 3 is a perspective view of a first embodiment of a couplingconnected to the inner cannula of FIG. 2;

FIG. 4 is a side elevation assembly view of the coupling and cannulas ofFIGS. 1-3;

FIG. 5 is a top plan assembly view from the line 5-5 of FIG. 4;

FIG. 6 is a side elevation view of the assembled coupling and cannulasof FIGS. 1-3;

FIG. 7 is a perspective assembly view of the leading end adapter of thecoupling of FIG. 3 and the outer cannula of FIG. 1;

FIG. 8 is a side elevation view of the assembled leading end adapter ofthe coupling of FIG. 3 and inner cannula of FIG. 2;

FIG. 9 is a trailing end elevation view of the assembly of FIG. 8;

FIG. 10 is a top plan view of the assembly of FIG. 8;

FIG. 11 is a leading end elevation view of the assembly of FIG. 8;

FIG. 12 is a leading end perspective view of the leading end adapter ofthe coupling of FIG. 3;

FIG. 13 is a trailing end perspective view of the leading end adapter ofthe coupling of FIG. 3;

FIG. 14 is a side elevation view of the leading end adapter of thecoupling of FIG. 3;

FIG. 15 is a trailing end elevation view of the trailing end adapter ofthe coupling of FIG. 3;

FIG. 16 is a top plan view of the leading end adapter of the coupling ofFIG. 1;

FIG. 17 is a leading end perspective view of the inner cannula of FIG. 2and leading end adapter of the coupling of FIG. 3 in an operativelyassembled condition;

FIG. 18 is a leading end perspective view of the inner cannula of FIG. 2and leading end adapter of the coupling of FIG. 3 in aready-to-disconnect condition;

FIG. 19 is a perspective assembly view of a second embodiment of thecoupling and inner cannula in relationship to a second type of knowntracheotomy tube outer cannula;

FIG. 20 is a top plan assembly view of the coupling and cannulas of FIG.19;

FIG. 21 is a trailing end view of the leading end of the coupling ofFIG. 19;

FIG. 22 is a leading end view of the leading end of the coupling of FIG.19;

FIG. 23 is a side elevation view of the leading end of the coupling ofFIG. 19;

FIG. 24 is a top plan view of the leading end of the coupling of FIG.19;

FIG. 25 is a side elevation assembly view of the cannulas and couplingof FIG. 19;

FIG. 26 is a side elevation view of the assembled cannulas and couplingof FIG. 19;

FIG. 27 is a perspective assembly view of a third embodiment of thecoupling in relationship to a third type of known tracheotomy tube;

FIG. 28 is a top plan assembly view of the coupling and tracheotomy tubeof FIG. 27;

FIG. 29 is a leading end perspective view of the coupling of FIG. 27 inan open condition;

FIG. 30 is a leading end elevation view of the coupling of FIG. 27 inthe open condition;

FIG. 31 is a top plan view of the leading end of the coupling of FIG. 27in the open condition;

FIG. 32 is a side elevation view of the leading end of the coupling ofFIG. 27 in the open condition;

FIG. 33 is a side elevation assembly view of the coupling andtracheotomy tube of FIG. 27;

FIG. 34 is a side elevation view of the coupling and tracheotomy tube ofFIG. 27 with the leading end of the coupling in the open condition;

FIG. 35 is a side elevation view of the assembled coupling andtracheotomy tube of FIG. 27;

FIG. 36 is a perspective assembly view of an improved child'stracheotomy tube and associated coupling;

FIG. 37 is a perspective assembly view of a fourth embodiment of thecoupling and an associated tracheotomy tube inner cannula;

FIG. 38 is a perspective assembly view of the assembled coupling andinner cannula of FIG. 37 in association with a corresponding knowntracheotomy tube outer cannula;

FIG. 39 is a side elevation assembly view of the coupling of FIG. 37 andthe assembled inner and outer cannulae of FIGS. 37 and 38;

FIG. 40 is a top plane assembly view of the coupling and inner cannulaof FIG. 37;

FIG. 41 is a side elevation view of the assembled coupling and inner andouter cannula of FIGS. 37 and 38;

FIG. 42 is a top plane view of the assembled coupling and inner andouter cannulae of FIGS. 37 and 38;

FIG. 43 is a cross-sectional view taken along the line 43-43 of FIG. 39;

FIG. 44 is a cross-sectional view taken along the line 44-44 of FIG. 39;

FIG. 45 is a cross-sectional view taken along the line 45-45 of FIG. 37;and

FIG. 46 is a cross-sectional view taken along a diametric plane of thecoupling of FIG. 37.

While the invention will be described in connection with preferredembodiments thereof, it will be understood that it is not intended tolimit the invention to those embodiments or to the details of theconstruction or arrangement of parts illustrated in the accompanyingdrawings.

DETAILED DESCRIPTION

Tracheal Inserts:

Adult tracheotomy tubes are illustrated in FIGS. 1-18, showing atracheotomy tube with outer and inner cannulas 100 and 130 and a taperedtubular extension 139 on the trailing end of the inner cannula 130 andFIGS. 19-26, showing a tracheotomy tube with outer and inner cannulas200 and 230 and a tapered tubular extension 223 on the trailing end ofthe outer cannula 200. A child's tracheotomy tube is illustrated inFIGS. 27-35. A child's tracheotomy tube has only one cannula which, forpurposes of explanation of the invention is identified as an outercannula 300.

All three known outer cannulas 100, 200 and 300 are, in some respects,substantially similar, being arced tubes 101, 201 or 301 ofapproximately a quarter circle extending from a leading end 103, 203 or303 to a collar 105, 205 or 305 at the trailing end 107, 207 or 307 ofthe arced tube 101, 201 or 301. A cuff 109, 209 or 309 on the leadinghalf of the arced tube 101, 201 or 301 is inflatable via an air supplyline 111, 211 or 311. The arced tube 101, 201 or 301 is the trachealinsert portion of the tracheotomy tube and, once inserted, the cuff 109,209 or 309 is inflated to hold and seal the tube 101, 201 or 301 inposition in the trachea. Each of the outer cannulas 100, 200 or 300 hasa neck plate 115, 215 or 315 which positions the outer cannulas 100, 200or 300 against the patient's neck and is adapted to maximize itsmanipulability relative to the collar 105, 205 or 305 by connectinghinges 117 or by openings 217 or contours 317 in its body. Each of theneck plates 115, 215 or 315 also has openings 119, 219 or 319 forconnection of an adjustable strap to pass around and secure the neckplates 115, 215 or 315 against the patient's neck. The adult outercannulas 100 and 200 are comparatively hard and the child's outercannula 300 is very soft. From the collars 105, 205 and 305 on thetrailing ends of the arced tubes 101, 201 and 301 toward the trailingends of the outer cannulas 100, 200 and 300, the configurations of theouter cannulas 100, 200 and 300 are quite different.

Both inner cannulas 130 and 230 are also, in some respects,substantially similar, being arced tubes 131 or 231 of approximately aquarter circle extending from a leading end 133 or 233 to a collar 135or 235 on a trailing end 137 or 237 of the arced tube 131 or 231. Theinner cannulas 130 and 230 are inserted at their leading ends 131 and231 into the trailing ends of their outer cannulas 100 and 200 untiltheir trailing ends mate. From the collars 135 and 235 toward thetrailing ends of the inner cannulas 130 and 230, the inner cannulas 130and 230 are quite different.

The outer cannulas 100, 200 and 300 and their associated known innercannulas have mechanisms which positively engage them against separationin their mated condition. They all present tapered tubular extensionsfor connection with known flexible connectors. The connection to knownflexible connectors is universally accomplished by mere insertion of atapered end of a tube into a constant diameter tube. The followingillustrated embodiments of the outer cannulas 100, 200 and 300 aresubstantially the same as the known outer cannulas. The illustratedembodiments of the inner cannulas 130 and 230 and the flexibleconnectors or couplings 160, 260 and 360 are substantially differentfrom the known inner cannulas and connectors so as to permit a positiveengagement of the outer cannulas with their flexible connectors.However, they have been configured to work with the known outer cannulas100, 200 and 300. The principles of the invention, however, are fullyapplicable to the connection of flexible connectors to outer cannulasother than those herein illustrated.

First Adult Tracheotomy Tube Embodiment:

Looking now at FIGS. 1-18, the first type of adult tracheotomy tube isillustrated. As best seen in FIG. 1, the collar 105 on the outer cannula100 has an annular ring 121 which is concentric about the trailing end107 of the outer cannula tube 101 and has top and bottom quarter arcs123 which extend concentrically on and in a trailing direction from thering 121. A concentric groove 125 is also provided in the face of thetrailing end 107 of the outer cannula tube 101.

Looking at FIGS. 1-3 and 8-11, the inner cannula 130 applies theprinciples of the invention to the outer cannula 100. A soft arced tube131 extends upwardly and rearwardly from its leading end 133 to a hardcollar 135 on its trailing end 137. The collar 135 tapers outwardly to awider, concentric, hard, tapered tubular extension 139 which extends ina trailing direction from the collar 135. The extension 139 taperstoward its trailing end face 141. The collar 135 has a pair ofdiametrically opposed latches 143, as shown appearing at approximatelythe 2 and 8 o'clock orientations when looking at the trailing end face141 of the inner cannula 130. The latches 143 have fingers 145 whichextend radially inwardly therefrom for engagement against the trailingface of the annular ring 121 on the trailing end 103 of the outercannula 100. The fingers 145 extend in the leading end direction fromresiliently flexible supports 147 on the collar 135. Squeeze plates 149extend in the trailing end direction from the fingers 145. The leadingfaces 151 of the fingers 145 are beveled so that, as the inner cannula130 is inserted into the outer cannula 100 and the beveled faces contactthe annular ring 121, the supports 147 flex to widen the distancebetween the fingers 145. Once the fingers 145 pass over the annular ring121, the supports return to their unbiased condition in which thetrailing faces of the fingers 145 engage the leading face of the ring121, thus locking the inner cannula 130 in place on the outer cannula100. The squeeze plates 149 provide suitable surfaces and leverage forthe thumb and forefinger to apply pressure to flex the support 147 andspread the fingers 145 so that the fingers 145 can be disengaged fromthe annular ring 121. The squeeze plates 149 have alignment indicia suchas arrows 153, as shown diametrically opposed and pointing in thetrailing end direction. As best seen in FIGS. 6, 8, 9, 11, 17 and 18,the collar 135 also has diametrically opposed rotational andlongitudinal ramps 155 and 157 and longitudinal beads 159 for reasonshereinafter explained.

Looking at FIGS. 1-16, the flexible connector 160 for use with the aboveouter and inner cannulas 100 and 130 has a leading end adapter 161, bestseen in FIGS. 5, 7 and 12-15. The leading end adapter 161 has a hardouter sleeve 167 with a soft tube liner 169. The trailing end 171 of thesleeve 167 is of narrower diameter so as to provide a connecting ring173 for reasons hereinafter explained. The outer sleeve 167 hasdiametrically opposed posts 175 on its wide circumference at the leadingend of the connecting ring 173. A pair of diametrically opposedresiliently flexible arms 177 extend longitudinally from the sleeve 167to radially inwardly extending fingers 179. The sleeve 167 also hasalignment indicia such as arrows 181 pointing in the leading enddirection. The flexible connector 160 is in proper rotationalorientation for connection to the outer and inner cannulas 100 and 130when the arrows 153 on the inner cannula 130 are aligned with the arrows181 on the connector sleeve 167. As best seen in FIG. 6, when the arrows153 and 181 are aligned, the connector arms 177 can pass under thesqueeze plates 149 of the inner cannula latches 143 with the flexibleconnector fingers 179 at approximately the 4 and 10 o'clockorientations. This positions the connector fingers 179 on the clockwiseside of the rotational and longitudinal ramps 155 and 157 when theconnector 160 is connected to the outer and inner cannulas 100 and 130.The leading faces 183 of the connector fingers 179 are beveled so that,as the flexible connector 160 is moved longitudinally into the taperedtubular extension 139 of the inner cannula 130, the fingers 179 will bespread apart by and slide across the ring 121, on the outer cannula 100.Once the fingers 179 pass the ring 121 they resiliently close to securethe flexible connector 160 to the outer cannula 100. The inner cannulacollar 135 is sandwiched between them.

As best seen in FIG. 12, the interior surfaces of the connector arms 177are provided with longitudinal grooves 185 and the counterclockwiseinside edges of the connector arms 177 are provided with longitudinalbevels 187. To remove the flexible connector 160 from the outer andinner cannulas 100 and 130, the connector 160 is rotatedcounterclockwise, as indicated by the rotational arrows 189, using thethumb and forefinger on the posts 175. As the connector 160 rotates, thelongitudinal bevels 187 on the connector arms 177 ride on the rotationalramps 155 on the inner cannula collar 135 to unlatch the connectorfingers 179 from the collar 135. The rotation is limited to the point ofabutment of the inner cannula and connector fingers 145 and 179,whereupon longitudinal beads 159 on the inner cannula collar 135 andgrooves 185 on the connector arms 177 engage to provide an audible clickindicating that the connector 160 can be longitudinally displaced anddisconnected from the outer and inner cannulas 100 and 130. As theconnector 160 is withdrawn in the trailing direction, the connectorfingers 179 ride on the longitudinal ramp 157 of the inner cannulacollar 135 to assure that the connector fingers 179 cannot relatchduring the process.

Second Adult Tracheotomy Tube Embodiment:

Turning to FIGS. 19-26, the other type of adult tracheotomy tube isillustrated. The collar 205 of the outer cannula 200 has a hard annularring 221 which is concentric about the trailing end 207 of the outercannula tube 201. The hard tapered tubular extension 223 of the ring 221narrows toward the trailing end 225. Top and bottom approximatelyquarter notches 227 are provided in the outer circumference of thetapered tubular extension 223 at the trailing end of the ring 221.

The inner cannula 230 applies the principles of the invention to theouter cannula 200. A soft arced tube 231 extends upwardly and rearwardlyfrom its leading end 223 to a concentric collar 235 on its trailing end237. A tapered tubular extension 239 extends in a trailing directionfrom the collar 235 to a trailing end face 241 of an annular ring 243 onthe extension 239. The outside wall of the extension 239 has annularridges 245 which complement the annular grooves 229 in the inside wallof the outer cannula tapered extension 223 to secure the inner cannula230 in place in the outer cannula 200. A pair of vertically alignedstuds 247 are provided on the trailing end face 241 of the inner cannulaextension 239 for reasons hereinafter explained. A concentric pull ring249 is hinged 251 to the bottom of the end face 241 of the extensions239 to facilitate removal of the inner cannula 230 from the outercannula 200. An annular outer flange 253 on the midportion of the innercannula arced tube 231 helps to hold the inner cannula tube 231concentrically within the outer cannula tube 201.

The flexible connector 260 for use with the above outer and innercannulas 200 and 230 has a leading end adapter 261, best seen in FIGS.21-24. The leading end adapter 261 has a hard outer sleeve 267 with asoft tube liner 269. The trailing end 271 of the sleeve 267 is ofnarrower diameter so as to provide a connecting ring 273 for reasonshereinafter explained. The outer sleeve 267 has a corrugated surface 275to facilitate manipulation of the flexible connector 260. Diametricallyvertically opposed arms 277 with radially inwardly extending fingers 279at their leading ends are defined by longitudinal slots 281 in thesleeve 267. The fingers 279 are contoured to engage in the opposednotches 227 in the outer cannula tapered tubular extension 223. As bestseen in FIG. 23, valleys 283 in the inner and outer surfaces of the arms277 at their trailing ends permit the arms 277 to flex easily. As bestseen in FIGS. 21 and 22, the leading face of the connecting ring 273 ofthe leading end adapter 261 has notches 285 which receive the studs 247on the trailing end face 241 of the inner cannula 230. The notches 285extend clockwise from the point of longitudinal insertion of the studs247 to stops 287. Counterclockwise rotation of the leading end adapter261 of the connector 260, indicated by the rotational arrows 289 on thesleeve 267, is terminated by the studs 247 striking the stops 287. Atthis point, the connector arms 277 will have flexed sufficiently todisengage the connector fingers 279 from the notches 227 in the outercannula extension 223 so that the connector 260 can be longitudinallywithdrawn from the outer and inner cannulas 200 and 230.

Child Tracheotomy Tube Embodiment:

Turning to FIGS. 27-35, the child's tracheotomy tube is illustrated. Asbest seen in FIG. 27, the collar 305 on the soft tube 301 has aconcentric annular ring 321 extending in a trailing direction with asoft tapered extension 323 extending in a trailing direction from thering 321. The extension 323 has annular ridges 325 in its circumferenceand a beveled flange 327 with an annular groove 329 in its trailing endface. A hard sleeve 331 is tapered to concentrically cover the taperedextension 323. The hard sleeve 331 has a pair of annular flanges 333 atits leading end defining an annular groove 335 therebetween. When thesleeve 331 is mounted on the soft tapered extension 323, the leadingface 337 of the sleeve 331 abuts the trailing end face of the ring 321on the collar 305 and the trailing end face 341 of the sleeve 331 abutsthe leading end face of the beveled flange 327 on the tapered extension323, locking the hard sleeve 331 in place on the soft extension 323.

Looking at FIGS. 27-35, the flexible connector 360 for use with thecannula 300 has a leading end adapter 361, best seen in FIGS. 29-32. Theleading end adapter 361 is a clamshell-type grip with bottom and topshells 367 and 369. The shells 367 and 369 extend from a trailing endface 371 on a trailing connecting ring 373 to a leading connecting ring375 separated by a narrower body 377. As best seen in FIG. 35, theshells 367 and 369 are defined by a radial cut 379 splitting the tophalf of the trailing connecting ring 373 and a horizontal diametric cut381 extending from the radial cut 379 through the leading connectingring 375. The shells 367 and 369 are hinged 383 at the top of the radialcut 379. The leading connecting ring 375 has grooves 385 defining aridge 387 which will engage in the groove 335 on the leading end of thehard sleeve 331 mounted on the soft tapered tubular extension 323 of thecannula 300. A tapered nozzle 397 extends in a leading direction fromthe leading face of the trailing connecting ring 373. The nozzle 397 hasan annular bead 399 on the perimeter of its leading face. A concentricbead 401 is provided on the leading face of the trailing connecting ring373 around the nozzle 397. The annular bead 399 on the nozzle 397 abutsthe inside wall of the soft tapered tubular extension 323 of the cannula300 and the concentric bead 401 on the leading connecting ring 375 seatsin the groove 329 on the leading face on the beaded flange 327 of thesoft tapered tubular extension 323 of the cannula 300 when the softextension 323 with the hard sleeve 331 are longitudinally inserted intothe clamshell of the connector 360. As best seen in FIGS. 29-32,flexibly resilient supports 403 extend radially outwardly from the topshell portion of the body 377 at the diametric cut 381. Arms 405 extenddownwardly, considering the clamshell in the closed condition of FIG.35, from each of the supports 403 to fingers 407 which extenddiametrically inwardly from the arms 405. The fingers 47 have beads 409on their upper inside edges. The arms 405 also extend upwardly from thesupports 403 to corrugated squeeze plates 411 which aid in manuallyflexing the arms 405 between the thumb and forefinger. To cooperate withthe fingers 407, L-shaped lugs 413 extend upwardly, again consideringthe clamshell in the closed condition of FIG. 35, from the bottom shellportion of the body 377 at the diametric cut 381. When the top shell 369is closed on the bottom shell 367, the fingers 407 snap under the lugs413 and the beads 409 engage the inside edges of the lugs 413 to assurea stable engagement.

The above described flexible connector 360 with the clamshell-typeleading end adapter 361 accomplishes the objects, aims and advantages ofthe present invention when used with known outer cannula only or childtracheotomy tubes 300. Such single cannula tracheotomy tubes 300,however, have hereinbefore noted deficiencies of their own. Inparticular, looking at FIG. 27, the hard sleeve 331 replaces themanufacturer's original hard sleeve (not shown) which rotates on thesoft extension 323 to allow some freedom of motion of the patient. Thisconfiguration focuses the dissipation of rotational forces at thepatient end of the tracheotomy system. Moreover, the original and thereplacement hard sleeve 331 are locked on the soft extension 323 by thebeveled flange 337 and cannot be removed, for cleaning or other reason,without use of a tool and application of force to the tracheotomy tubeand, consequently, the patient. Therefore, turning to FIG. 36, animproved child's tracheotomy tube 500 and connector 560 are illustratedwhich transfer the rotational capability to the connector 560, so thatfreedom of motion is maintained and the connector 560 can bedisconnected from the tracheotomy tube 500 without applying rotationalor longitudinal forces to the tracheotomy tube.

As seen in FIG. 36, the tracheotomy tube 500 is a unitary arrangement ofa soft tube 501 formed by a silicone case on a coil of titanium or othernon-iron based wire so that the improved tracheotomy tube 500 iscompatible with MRI procedures. The soft tube 501 trails to a neck plate515 with an annular ring 521 on its trailing side. A soft extension 523trails concentrically from the annular ring 521 to a trailing annularflange 525 having the same diameter as the annular ring 521. Preferably,the soft extension 523 is covered up to the soft flange 525 by a hardsleeve 531 which is permanently fused to the soft extension 523. Theannular ring 521 has a plurality of circumferential sets ofdiametrically opposed serrations 543, preferably and as shown transverseto and straddling the 3 and 9 o'clock diametric plane of the annularring 521.

Continuing to look at FIG. 36, the flexible connector 560 has a leadingend adapter 561 and a trailing end adapter 563 on the ends of anintermediate tube 565. The leading end adapter 561 is a hard sleeve witha trailing end annular wall 567. A pair of diametrically opposed latches571 have flexible supports 573 which extend radially outwardly from theleading end adapter 561 to forwardly extending arms 575 with inwardlyradially extending fingers 577. As shown, the latch fingers 577 straddlethe 3 to 9 o'clock plane so as to be co-operable with the serrations 543on the tracheotomy tube annular ring 521. This orientation is preferredso as to reduce the likelihood of the application of pressure by thechin and chest of the patient to the latches 571. The fingers 577 areengagable in the serrations 543 on the tracheotomy tube annular ring 521to secure the connector 560 to the tracheotomy tube 500 when the softflange 525 of the tracheotomy tube extension 523 is in abutment with thetrailing end annular wall 567 of the leading end adapter 561. The walls545 formed by the annular ring 521 at the ends of the serrations 543prevent any significant rotation of the leading end adapter 561 inrelation to the tracheotomy tube 500. The plurality of circumferentialsets of serrations 543 allows tolerance for the lengths of the leadingend adapter 561 and the tracheotomy tube extension 523. The latches 571also have rearwardly extending squeeze plates 579 which provide suitablesurfaces and leverage for the thumb and forefinger to apply pressure toflex the supports 573 and spread the latch fingers 577 so that theconnector 560 can be disengaged from the tracheotomy tube 500 withoutneed for exertion of excessive rotational or axial force on thetracheotomy tube 500.

The trailing end adapter 563 has a hard annular ring 581 on its leadingend with a tubular concentric rearward extension 583. The extension 583has an outer annular groove 585 on its mid-portion, an annular flange587 on its outer trailing end and a plurality of slots 589 extendingaxially in its wall from its trailing end toward the groove 585 toprovide a plurality of flexible fingers 591 with beveled tips 593. AnO-ring 595 is seated in the groove 585. A sleeve 597 has a diametersuitable for sliding over the beveled tips 593 of the fingers 591 toradially depress the fingers 591 toward each other and receive thesleeve 597 fully on the extension 583. The sleeve 597 has an innerannular groove 599, preferably of cross-section which complements thecross-section of the beveled tips 593 on the trailing end of the sleeve597. When the sleeve 597 is fully on the extension 583, the fingers 591spread outwardly and the beveled tips 593 engage in the complementalgroove 599 to prevent the sleeve 597 from sliding off the extension 583.The sleeve 597 is free to rotate on the extension 583, rotation beingfacilitated by the O-ring 595. The outer diameter of the sleeve 597 istapered toward its trailing end to facilitate connection to theventilator tube (not shown).

Third Adult Tracheotomy Tube Embodiment:

Turning to FIGS. 37-46, an adult tracheotomy tube embodiment isillustrated which includes an inner cannula 630 and a flex connector 660for use with an outer cannula 600 which is a modification of the outercannula 100 of the first adult tracheotomy tube of FIGS. 1-18. Lookingat FIG. 38, this modified outer cannula 600, similar in many respects tothe outer cannula 100, has an arced tube 601 which extends from itsleading end 603 to a collar 605, seen in FIG. 39, at its trailing end607. On the collar 605 is an outer annular flange 609 with a trailingportion 611 and a leading portion 613. As best seen FIGS. 41 and 42, theleading portion 613 of the flange 609 has recessed upper and lower seats615 and the flange 609 is divided into upper and lower portions definedby leaves 617 which extend outwardly from the flange 609 above and belowthe seats 615. Between the leaves 617, the flange 609 provides sideseats 619.

The known inner cannula (not shown) presently used with theabove-described known outer cannula 600 functions similarly to otherknown inner cannulae in that it is intended to be securely latched tothe outer cannula 600 and to be and slip connected to the leading end ofits ventilator tube connector. The slip connection is the result oflongitudinal insertion of the trailing end of the inner cannula (notshown) into the leading end of the ventilator tube connector, theventilator tube connector and the inner cannula being frictionally heldin this relationship. Thus, the known combination of these inner andouter cannulae requires the exertion of longitudinal forces to create orterminate the frictional condition necessary to slip connect the innercannula to the ventilator tube connector of the assembly and to separatethem after they have been connected. Furthermore, this slip connectionachieved by friction does not reduce the likelihood of inadvertentseparation of the ventilator tube connector from the tracheotomy tube.

Turning to FIG. 37, an improved inner cannula 630 for use with the outercannula 600 is illustrated. The inner cannula 630 has an arced tube 631extending from its leading end 632 to a collar 633, best seen in FIG.40, at its trailing end 634. As seen in FIG. 37, the inner cannula 630also has a tubular extension 635 at its trailing end 634. The extension635 includes an inner soft sleeve 636 trailing from the collar 633. Thesoft sleeve 636 is contained within a hard outer sleeve 637, the outersurface of which is preferably narrowingly tapered from the collar 633to its trailing end face 638. As best seen in FIG. 44, the inside wallof the hard outer sleeve 637 and the outside wall of the soft innersleeve 636 have alternating splines and grooves 639 to prevent rotationof the hard outer sleeve 637 about the soft inner sleeve 636. Lookingagain at FIG. 37, the leading end of the hard outer sleeve 637 has apair of opposed latches 641 for coupling the inner cannula 630 to theouter cannula 600. Each of the latches 641 has a base 642 on the outerwall of the hard sleeve 637 with a resiliently flexible post 643 whichacts as a fulcrum for operation of the latch 641. Squeeze plates 644extending rearwardly of the fulcrum 643 are used to manipulate fingers645 which are contoured to engage with the side seats 619 on the outercannula flange 609, as seen in FIG. 42. The leading faces 646 of thefingers 645 are beveled and the width of the squeeze plates 644 andfingers 645 is such that the latches 641 can be inserted between theopposed leaves 617 of the outer cannula flange 609, as seen in FIG. 38.The bases 642 of the latches 641 have outwardly extending posts 647which are cooperable with strikers 648 which extend inwardly from thesqueeze plates 644 to limit the stroke of the squeeze plates 644. Whenthe cannulae 600 and 630 are connected, the leaves 617 on the outercannula flange 609 limit rotation of the inner cannula 630 within theouter cannula 600 so that the inner and outer cannulae 600 and 630cannot be separated inadvertently, but only by intentional operation ofthe latches 641 to release the outer cannula 600.

As best seen in FIGS. 40, 41 and 45, the outer surface of the hardsleeve 637 of the inner cannula 630 has a pair of radially extendingflanges 651, as shown angularly aligned between the latches 641 andpositioned axially rearwardly thereof. Each of the inner cannula flanges651 has side ramps 652 and a rear ramp 653 defining a U-shaped retainingseat 654. As best seen in FIG. 45, the side ramps 652 are tapered awayfrom each other on the inside of the seat 654 and, as best seen in FIG.39, the rear ramp 653 is tapered toward the leading end of the hardsleeve 637. Looking at FIG. 44, directional arrows 655 on the rear ramps653 point axially to the rear centers of the rear ramps 653.

In FIGS. 37, 39, 40, and 46, the flex connector 660 for use with theinner cannula 630 is shown disconnected from the inner cannula 630. Aswith the previously described connectors 160, 260, 360 and 560, theflexible connector 660 has a leading adapter 661, a trailing end adapter663 and a tubular member 665 extending between the adapters 661 and 663.

The flex connector 660 has a leading end tubular portion 669 and atrailing end tubular portion 671 on opposite ends of the accordion-typeflexing tubular member 665. The end portions 669 and 671 of the flexingtubular member 665 line the inside walls of the hard adapters 661 and663. The leading end tubular portion 669 has an outer flange 672 on itsleading rim and a wider outer diameter 673 proximate its trailing end.The trailing end tubular portion 671 has a trailing end portion 666 withan outer flange 668. The flexing tubular member 665 allows the connector660 to expand and contract in accordion fashion and to bend up toapproximately 90 degrees or more.

The leading end adapter 661 of the connector 660 is a hard sleeve 667with annular seats 662 and 664 in its leading and trailing faces. Thesofter leading end tubular portion 669 is force fitted into the hardsleeve 667 and the outer annular flange 672 and wider diameter 673 onthe end portion 669 engage in the annular seats 662 and 664 on the hardsleeve 667 to prevent the leading end adapter 661 from sliding off theleading end tubular portion 669 of the flex connector 660.

The trailing end adapter 663 of the connector 660 is a hard sleeve 692with a leading outer annular flange 693 and a larger inner diameter 694on its trailing portion 695. The trailing end adapter 663 is manipulableby use of the annular flange 693 on its hard sleeve 692 to press thehard sleeve 692 into the leading end of the ventilator tube. The flexingtubular member 665 allows this to be accomplished without exertion ofundue axial force on the cannulae 600 and 630 or the patient. The softertrailing end tubular portion 671 is force fitted into the hard sleeve692 and the annular flange 668 impinges upon the change in innerdiameter 694 to prevent the trailing end adapter 693 from sliding offthe trailing end tubular portion 671 of the flex connector 660.

The outer surface of the hard outer sleeve 667 of the leading endadapter 661 has a plurality of longitudinal ridges 675 to facilitatemanipulation and rotation of the leading end adapter 661. A pair ofresiliently flexible arms 677 extend forwardly of the leading endadapter 661 and are angularly positioned for alignment with theretaining seats 654 formed in the flanges 651 on the outer surface ofthe hard sleeve 637 of the inner cannula tubular extension 635. The arms677 are fixed at one end on the hard outer sleeve 667 of the flexconnector 660, extend longitudinally to posts 682 which space the arms677 radially outwardly from the hard outer sleeve 667 and extendforwardly from the posts 682. As best seen in FIG. 39, the arms 677 havebeveled leading faces 679 which are cooperable with the rear ramp 653 onthe inner cannula tubular extension 635 to spread the arms 677 when theleading end adapter 661 is slipped onto the inner cannula tubularextension 635. The sidewalls 684 of the fingers 678 are also beveled, asbest seen in FIG. 43. When the fingers 678 are engaged in the retainingseats 654 of the inner cannula flange 651, the beveled finger sidewalls684 cooperate with the beveled interior side ramps 652 of the retainingseats 654 in the inner cannula flanges 651 and spread the arms 677during rotation of the leading end adapter 661. Thus, disengagement ofthe flex connector leading end adaptor 661 from the inner cannula 630 isaccomplished by use of rotational motion of the adapter 661.

As shown, the leading end adapter 661 has axial directional arrows 685on its arms 677 which will align with the axial arrows 655 on the rearramps 653 of the inner cannula flanges 651 when the fingers 678 arealigned to engage in the retaining seats 654. The leading end adapter661 is also provided with rotational arrows 687 as a reminder thatdisengagement of the flex connector 660 from the inner cannula 630 isaccomplished by exertion of rotational rather than axial forces on theleading end adapter 661.

The improved coupling 660 and its leading end adaptor 661 have beendescribed in relation to connecting an inner cannula 630 to a ventilatortube. However, the coupling 660 could be used to connect any air supplyto any of a variety of respiratory support devices if they are providedwith radially outwardly extending flanges. Such devices include, but arenot limited to, tracheotomy tube cannulae, endotracheal tubes, laryngealmask apparatus, combitubes, airway pressure masks, resuscitation bags,and ventilator connectors such as elbows and step-up and step-downconnectors and heat-moisture exchangers.

Common Connector Components:

Each of the flexible connectors 160, 260, 360, 560 and 660 has its ownunique leading end adapter 161, 261, 361, 561 and 661 as abovedescribed. The trailing end adapters 163, 263, 363 and 663 andintermediate tubes 165, 265, 365 and 665 for the flexible connectors160, 260, 360 and 660, used with existing adult tracheotomy tubes 100,200 300 and 600 are substantially the same. The trailing end adapters163, 263, 363 and 663 have hard tubular extensions 193, 293, 393 and 693with annular flanges 195, 295, 395 and 695 to facilitate manipulation ofthe connectors 160, 260, 360 and 660 during attachment to theventilator. The trailing end adapters 161, 261, 361 and 661 are fixed tothe trailing ends of their intermediate tubes 165, 265, 365 and 665,also as by ultrasonic welding.

The intermediate tube 565 used with the improved child's tracheotomytube 500 is substantially the same as the intermediate tubes 165, 265,365 and 665 of the other flexible connectors 160, 260, 360 and 660. Theleading and trailing end adapters 561 and 563 are different.

Common Operational Features of the Embodiments:

For each of the different tracheotomy tube outer cannulas 100, 200 and300, the corresponding coupling 160, 260 and 360 has a leading endadapter 161, 261 and 361 which interlocks with its respectivetracheotomy tube outer cannulas 100, 200 and 300 preventing them frominadvertently axially displacing from each other. However, non-axialforce applied to the unlatching mechanism disengages the associatedadapter 161, 261 or 361 from its tracheotomy tube outer cannula 100, 200or 300 so that the coupling 160, 260 or 360 can be axially displacedwithout exertion of excessive axial force on the system and the patient.

Similarly, for the improved tracheotomy tube 500, its correspondingcoupling 560 has a leading end adapter 561 which interlocks with itstracheotomy tube 500 to prevent them from inadvertently axiallydisplacing from each other. However, non-axial force applied to theunlatching mechanism disengages them so that the coupling 560 can beaxially displaced without exertion of excessive axial force on thesystem and the patient. While the improved tracheotomy tube 500 has beendescribed as being intended for children, this designation is based onthe heretofore accepted view that an adult tracheotomy tube has innerand outer cannulas and that a child's tracheotomy tube has a singlecannula. However, the improved cannula 500 can be sized for use bychildren or adults.

For the third adult tracheotomy tube outer cannula 600, thecorresponding coupling 660 has a leading end adapter 661 whichinterlocks with its tracheotomy tube inner cannula 630, preventing themfrom inadvertently axially displacing from each other. However,non-axial force applied to the unlatching mechanism disengages theadapter 661 from its tracheotomy tube inner cannula 630 so that thecoupling 660 can be axially displaced without exertion of excessiveaxial force on the system and the patient.

Thus, it is apparent that there has been provided, in accordance withthe invention, a ventilator to tracheotomy tube coupling that fullysatisfies the objects, aims and advantages set forth above. While theinvention has been described in conjunction with specific embodimentsthereof, it is evident that many alternatives, modifications andvariations will be apparent to those skilled in the art and in light ofthe foregoing description. Accordingly, it is intended to embrace allsuch alternatives, modifications and variations as fall within thespirit of the appended claims.

What is claimed is:
 1. For connecting an air supply to a respiratorysupport device having radially outwardly extending flanges proximate atrailing end thereof, a coupling comprising: a flexing tubular member;means on a trailing end of said flexing tubular member for connectingsaid coupling in a pneumatic flow path to the air supply; means on aleading end of said flexing tubular member for mating said coupling insaid pneumatic flow path with the respiratory support device by motionof said means for mating in a generally axial direction toward therespiratory support device to bring a leading face of said flexingtubular member into abutment with a trailing face of a trailing end ofthe respiratory support device; and means on said means for mating forengaging with the flanges of the respiratory support device when saidflexing tubular member and the trailing face of the respiratory supportdevice are in abutment to prevent said flexing tubular member fromaxially displacing from the respiratory support device.